public void TakeMoreThanAvailableShouldThrow()
        {
            var storage = new CommodityStorage();

            storage.Deposit(grain, 2);
            storage.Withdraw(grain, 3);
        }
        public void SimpleCommodityStorageTest()
        {
            var storage = new CommodityStorage();

            Assert.AreEqual(0, storage[grain]);
            storage.Deposit(grain, 2);
            Assert.AreEqual(2, storage[grain]);
            storage.Withdraw(grain, 1);
            Assert.AreEqual(1, storage[grain]);
        }